On November 10, 2025, the Post Office announced yet another extension of its contract with Japanese tech giant Fujitsu, agreeing to pay an additional £41 million to keep the controversial Horizon IT system running until at least March 2027. This decision—hardly a surprise to those following the saga—has reignited public and political anger over the Post Office’s continued reliance on a system at the heart of one of the UK’s most notorious miscarriages of justice.
The Horizon system, developed by Fujitsu and introduced in the late 1990s, was meant to modernize accounting across thousands of Post Office branches. Instead, it became infamous for generating unexplained discrepancies in branch finances, leading to more than 900 subpostmasters being wrongly prosecuted for theft, fraud, and false accounting. As Computer Weekly first revealed back in 2009, these prosecutions destroyed lives and livelihoods, earning the scandal the grim title of the most widespread miscarriage of justice in British history.
Despite a High Court ruling in 2019 that found Horizon was riddled with bugs, errors, and defects, and a public inquiry that has laid bare the system’s failings, the Post Office has found itself unable to break away from Fujitsu’s grip. According to BBC News, the latest extension follows a December 2024 contract that was supposed to keep Horizon running only until March 2026. But with no replacement supplier ready, the Post Office had little choice but to negotiate another bridge deal with Fujitsu.
“We are committed to moving away from Fujitsu and off the Horizon system as soon as possible. We are bringing in a different supplier to take over Horizon while a new system is developed, and this process is well underway,” a Post Office spokesperson told the press. The plan, they said, is to award a contract for a new supplier to manage Horizon by July 2026, but sources cautioned the transition could drag on until 2028.
Attempts to replace Horizon have been anything but smooth. The Post Office’s in-house project, dubbed NBIT, was abandoned after costs ballooned from an estimated £180 million to a staggering £1.1 billion—an eye-watering sum that drew sharp criticism from government watchdogs and the public alike. In May 2025, a government tender offered £323 million to a new replacement services provider and £169 million for commercial off-the-shelf software, but the procurement process is still in its early stages.
Meanwhile, Horizon continues to wreak havoc on branch accounts. Over the past two years, subpostmasters have identified more than 16,000 discrepancies, including both shortfalls and surpluses, according to a freedom of information response obtained by Computer Weekly. In its most recent financial year alone, the taxpayer-owned Post Office wrote off £11.6 million in unidentified shortfalls, following £10.4 million the year before. Millions of pounds simply vanished into the system’s digital ether, with no clear explanation.
At the ongoing public inquiry into the scandal, Paul Patterson, Fujitsu’s European head, didn’t mince words about the system’s decrepit state. “Some parts of Horizon are so old that Fujitsu doesn’t want to turn them off as it is uncertain what would happen if it did,” he testified in November 2024. Patterson also admitted, “Fujitsu had a moral obligation to contribute financially” to the redress for victims, but so far, no concrete timeline or figure has been set.
The relationship between the Post Office and Fujitsu has grown increasingly tense. Patterson told the inquiry he did not trust the Post Office and that any contract extension “must be as short as possible.” Yet, with the Post Office unable to find a viable alternative, Fujitsu’s leverage remains considerable. As one peer, James Arbuthnot, put it, “Are we so dependent on them? What does that say about our bargaining power, or about our resilience?”
The government, for its part, has tried to reassure the public that change is on the horizon—pun intended. “We are working as quickly as possible to ensure the Post Office has the technology it needs, including replacing Horizon, as a vital part of the company’s wider transformation,” a government spokesperson said. But critics argue that the very fact Horizon is still in use reflects years of under-investment and a lack of urgency in addressing the system’s deep-rooted flaws.
The anger isn’t limited to the technical failings. For years, the Post Office and Fujitsu deflected blame, even as mounting evidence showed Horizon’s unreliability. Subpostmasters found themselves presumed guilty, their protests dismissed, and their reputations ruined. Only after a relentless campaign by victims, journalists, and Members of Parliament did the truth come to light. The High Court’s findings and subsequent public inquiry have exposed a culture of denial and cover-up at the highest levels of both organizations.
Public and political pressure continues to mount. Many are calling for Fujitsu to be barred from future government contracts until it makes good on its promise to help compensate victims. The taxpayer has already footed a significant portion of the bill, and with the cost of compensation schemes expected to exceed £1 billion, the demand for accountability is growing louder. Some MPs have even suggested that individuals responsible for the scandal should face criminal charges.
The timeline of the Horizon debacle reads like a cautionary tale of institutional inertia and misplaced trust in technology. From the first warning signs in the late 1990s, to the legal battles of the 2010s, to the slow drip of revelations in the public inquiry, each chapter has exposed new layers of failure. As recently as June 2024, former subpostmasters in Scotland had their convictions quashed, and campaigners continue to fight for fair compensation and full exoneration for all victims.
Despite Fujitsu’s apologies and the Post Office’s promises of reform, the road to justice and technological renewal remains long. With the Horizon system now officially at its “end of life” but still deeply embedded in daily branch operations, the risk of further errors—and further injustice—remains uncomfortably high. For the hundreds of subpostmasters whose lives were upended, and for the public footing the bill, the wait for closure drags on.
As the Post Office embarks on yet another attempt to modernize its IT infrastructure, the lessons of the Horizon scandal loom large. Trust, transparency, and accountability—qualities sorely lacking in the past—will be essential if the organization is to restore its battered reputation and finally deliver justice to those it wronged.
